Whilst updating the resource I had another idea that I thought teachers might find to be helpful.
As you may know, you can drag left and have the resource make random selections from your groups - one students at random from each group, for example, to act as a group leader.
However, I thought it could be helpful at times to be able to make manual selections - so that you can choose a leader for each group (rather than the process being random).
When students are in groups, simply click a name to select it - very easy!
In the example below, I click to select (and then click to deselect!) Ayesha, Rose-Merline, Junior, Pierre and Chloé to be group leaders: